Mammut magic slings???

At the risk of continuing the beat this horse...

I'm not familiar with these new sheathed webbing slings. Never even held one in my hands. But this talk about knotting them (to join ends to make a loop) reminds me of now-old testing of Spectra-core 5mm cord when it first came out. IIRC a double fishermans used to join this type of cord failed b/c as the knot is pulled and inevitably stretches a bit, the slippery core strands pull out of the knot. Eventually the knot is nothing but the nylon sheaths. That breaks and the thing fails. A triple fisherman's was recommended as the solution, and we all fell in line. But Technora, aramid blends and the like seem to have replaced pure Spectra-core cords since then.

So I guess I'm asking - have these "kernmantle webbings" been tied and pull tested? Are they not sold except as sewn slings (a la Dyneema slings) to discourage tying them into loops?

http://dmmclimbing.com/knowledge/knotting-dyneema-vid/

dmm testing knotted dyneema, note how the dynamic drop test yielded lower breaking point than the static pull test and they only tested the triple fisherman's knot dynamically.   So we can infer that in a dynamic fall a water not (overhand) in 8mm dyneema would hold less than 6kn.  Possibly 30% less like the triple fishermans, which would be around 4kn or no good for any part of an anchor imo

sorry thats not related to the mammut slings, i guess they are sposed to hold knots better?

I’ve used a dyneema sling to backup a rappel. I’ve jugged a rope with a cord and a dyneema sling..

Yer gunna die!!

Zacks wrote:

except that if the sling actually did brake the whole point of the knot is to make it redundant, I know a broken sling is unlikely but wear and tear sharp edges ect, things happen.  So if the sling broke it would be just like a sling tied back into a loop.  Sure maybe the dyneema knot would hold, but also maybe it wouldn't, why bother when other options are so easily available, not to mension untying skinny loaded dyneema knots is annoying.

if you wanna go overboard, there is always the blue water titan runner.  its a mix of spectra and nylon so it holds knots, half way between nylon and dyneema for bulk factor and they are rated to 27kn so even after you lose some strength with knots it will still be pretty high 27-40% is still 16.2kn... more than my cams lol

https://www.rei.com/product/474003/bluewater-titanspectra-runner-916

I'm a big fun of Titan runners, they're bulkier but extremely burly and durable, very confidence inspiring. I usually carry two of them and use them for two-bolt anchors. The material holds knots, either overhand or figure-8, reliably. I also carry a 12' Titan rabbit runner (single strand with sewn loops on each end) which I occasionally use to extend a far away piece, as a backup to a cordelette, and for various miscellaneous or emergency uses such as a 3:1 hauling system (the static material works way better than a rope or a strand of cordelette).

But I would trust a master point knot in pretty much any spectra / dyneema sling. It's a different knot and different scenario than a fisherman's bend. I think the biggest issue with tying an overhand or figure-8 master point in dyneema slings is that because they are thinner and more slippery, the knot will get very tight, and be harder to untie after. I think the figure-8 knot has a big advantage over the overhand in being both more secure and easier to untie, so if you're concerned, just stick to that.

Gunkiemike wrote:

"Tech webbing is super-thin, super-strong webbing that has a braided polyamide sheath and a Dyneema® core. Dyneema is light material with high tensile strength, but it abrades rapidly and its slipperiness does not hold knots well. The addition of a polyamide sheath increases the stability and safety of knots and hitches."
Sold by the metre: https://www.mec.ca/en/product/5027-682/12mm-Nylon-Dyneema-Flat-Tech-Webbing

Dan Africk wrote:

But I would trust a master point knot in pretty much any spectra / dyneema sling. It's a different knot and different scenario than a fisherman's bend. I think the biggest issue with tying an overhand or figure-8 master point in dyneema slings is that because they are thinner and more slippery, the knot will get very tight, and be harder to untie after. I think the figure-8 knot has a big advantage over the overhand in being both more secure and easier to untie, so if you're concerned, just stick to that.

If you're concerned about untying the sling after being knotted just clip a carabiner inside the knot. That makes it trivial to untie even with an overhand and also gives you an additional clip-in point. 

John Wilder wrote:

Fail? I've used their slider lockers and have been using them since they were released (I used to work for them)- the original versions tended to stick open, but the new ones have fixed the issue and the old ones were easily closed with a light tap.  I've never heard of one actually failing in use if the gate was closed (and I can't imagine how it would- its a regular carabiner). 

For your own reference- Edelrid invented the kernmantle rope, so their soft good tech is the among best out there. Their hard goods are all made by Climbing Technologies in Italy, including the slider. 

Failed as in the locking mechanism (the sliding piece and spring) popped out suddenly and without warning, instantly turning my locking carabiner into a non-locker. There was no damage or impact or anything else that should have caused this. This happened when I was using it to secure myself to an anchor before untying the rope and preparing to rappel, luckily I caught it right before trusting my life to this carabiner. To add insult to injury, before the loose spring completely popped off, it snagged and damaged my brand new PAS, pulling out a loop of thread. 

When I contacted Edelrid they told me this had happened at least once before, but that they had fixed the issue with the newer version of the carabiner. But somehow they didn't seem to think the users of the thousands of older model carabiners deserved a recall or even a warning about this danger. They said didn't consider this a danger since when the locking mechanism fails it still works as a non-locking carabiner. I find this logic pretty twisted, because if someone is using a locking carabiner it is because they consider the locking aspect necessary and are relying on it for safety, and having it suddenly turn into a non-locker without warning is a pretty big deal to me.. 

So yeah a known issue with multiple documented failures, and they refused to issue a recall or warning of any sort. Edelrid also refused to replace or pay for my gear that was damaged as a result of their product failure (instead they recommended I fix it by melting the loose threads with a lighter, which seems like risky advice..). They offered to replace that one damaged carabiner if I sent it in, but I was not interested in giving up the evidence or getting another crappy carabiner that I wouldn't use anyway. I'm very forgiving of companies that make a mistake but handle it in a responsible fashion. DMM had a recall recently and is a great example for how companies should behave, I actually trust them and their products even more as a result. I will never buy another Edelrid product in my life if I can help it, I don't give a damn what history they have inventing the kernmantle rope.

PS- Oh yeah, the slider also sticks open, on both the old and the new version. If anything it's worse on the newer version.

Also, apologies for the completely off-topic tangent..

John Wilder wrote:

Yes, this is true. Mammut has the lowest nylon to dyneema ratio with their 8mm slings- and yes, the colored part is nylon and white is dyneema because dyneema cannot hold a dye. Mammut used to make a 6mm dyneema sling with barely any nylon, but they weren't durable enough and they discontinued them after a couple years. These days, the 8mm Mammut and 10mm BD seem to be the most common.

That said, you cant tie a regular dyneema sling (with white showing) into a knot as the dyneema will slip and the know will fail. It is a known limitation of dyneema slings.

the Edelrid Tech Web have a nylon sheath and a dyneema core, allowing the sling to be cut and tied into a knot. The nylon is what allows the knot to be tied while the inner core keeps the strength rating at 22kn. They're a little fatter than dyneema, but skinnier than any regular nylon sling- and cheaper than a dyneema sling as well, which makes for a pretty great compromise, imho.

edit: The Mammut Magic Sling is likely to have a nylon sheath and aramid core, similar to the Tech Web. Mammut's tech is essentially the same thing as the Tech Web, except its stiffer, more expensive, and bulkier than the Edelrid version. 

Just a couple notes.  UHMWPE can hold a dye (see https://www.marlowropes.com/product/d12-99-dyneema-grand-prix-rope, for instance): it just doesn't do it very well.  But plenty well enough that a red purchase will only be pink after years of running over blocks and sitting in the sun.  

Second, you can, of course, tie a regular dyneema sling in such a way that it will not slip (though it will still break at the knot).  There are several bends that are suitable for very slick materials.  Noobs: don't try this, you will actually die.  John, I'm guessing you know that and didn't want to encourage idiots to try, but figured I would set the record straight for those reading for informational purposes.  

Finally, the Magic Slings have UHMWPE cores (ie, Dyneema/Spectra), not Aramid cores.  Same with Edelrid's Tech Web.  It's an important distinction, as the properties are significantly different.  

John Wilder wrote:

I should also note that the slider is a great belay carabiner, but imho, it should never be used as a untended locker due to how the mechanism works and how easily it opens with something rubbing against the gate. 

I agree that it should not be left untended. Especially since if it opens accidentally, the gate will likely stick open. Even before this incident, I viewed the slider carabiner as halfway between a locker and non-locker in terms of security. I used one for my PAS, a use where an easy one-handed auto-lock mechanism made sense, and it would never be out of sight. I also sometimes used one for my autoblock, and for clipping my pack to the anchor when I bring one. I don't think the locking mechanism is secure enough to be used for belay, even aside from the failure, but I don't think it's crazy to use it for that. 

I think I understand your view about the safety issues of non-locking carabiners, but I disagree. What if the lock fails while you are using it to rappel or belay from? What if you're using it to hold an ATC in guide mode? It's not always possible to simply add another carabiner, and you may not even notice right away. At the very least, it's an issue that owners of these carabiners have a right to be aware of, and it boggles my mind how anyone could think that this known issue doesn't at least warrant a warning. 

I consider their approach in this matter to be despicable and shows an utter disregard for the safety of their customers. Who knows how many other safety issues their have been with their products that they never told us about because they just don't think it's a big deal with their 'European mindset'. I urge everyone to boycott Edelrid until they either go out of business or begin to act in an ethical fashion. Their are thousands of these older carabiners in the world that people are trusting with their lives.

John Wilder wrote:

No, man. Did you read what I wrote? 

Dyneema is slippery, not weak. 

Agreed, but if we're resting on the limiter knot of the quad clipped into two strands, and the knot comes untied due to slip, there's a 50/50 chance we're not clipped into anything at that point, so the strength of the dyneema won't come into play.

I'm NOT saying the quad is unsafe here, I'm just saying that the hard and fast rule of "don't trust knots in dyneema" doesn't make a lot of sense if we're trusting knots in dyneema in this situation (and others).

EDIT: Okay, reread, it looks like I did misunderstand, although Gunkiemike had already clarified what I was misunderstanding on the previous page. It sounds like you were just talking about re-tying a cut sling.

I got a Magic Sling on a whim with my REI dividend. It replaced a Titan sling that had gotten damaged in a rockfall. Both are overkill for most situations, and I would never build a rack out of them, but I like to have at least one burly sling with me. I use it in those rare cases where there's a single point of failure—extending my rappel, for example—and when there's increased risk of abrasion.

The Magic Sling is stiffer and a bit harder to knot than the Titan, but I do feel quite a bit more confident in its longevity. The Titan has a high strength rating, but it's still just as susceptible to damage as any other sling (as I discovered when a boulder took a chunk out of it). The Magic Sling isn't just strong, it's durable—the weight-bearing portion is protected by the outer sheath. 

John Wilder wrote:

 I can again assure you that they have restaffed with an American crew that is doing a fine job. I would encourage you to contact the North American office and talk with them if you have any further concerns. Chances are high the person you talked with no longer works for Edelrid (I'm fairly sure I know who it was), and the support structure behind him has been changed to a fully independent entity from Scarpa NA (their distributor from 2013-2015). If you would like, i'd be happy to facilitate your communications with them- shoot me a pm if you like.

The carabiners are still out there in the world, and Edelrid has still not issued a recall. Or said a word publicly about this known issue. I appreciate your offer to facilitate communication, but what they need to do is clear, and if no one currently working there has the integrity to do the right thing (which at this point has to include why they delayed a recall for several years..), I doubt another email from me or you is going to compel them to do so. After several years it would only make them seem more negligent to go public about this now. But hey if you want to email them and remind them that this is an issue, that would be great. 

This isn't something they can resolve with me. I'm aware of the danger with those carabiners. It's everyone else who owns these carabiners and is unaware of the danger I'm concerned about. And if they could get around to paying for my damaged gear (which I replaced after that incident), better late than never, that would just be icing on the cake.

Dear Dan Africk:

Your behavior here is one of my main problems with MP: 

WTF does Edelrid carabiners have to do with Mammut slings?!?!!?

And then you keep arguing. Create your own thread.  

And show respect for the OP, those of us who took the time to reply on topic and everybody else who reads here.

@Will Shelton: Good video I came across when googling `mammut magic sling vs sling` which also brought me to this post. Hope this helps you, albeit about 3yrs later :P

https://www.youtube.com/watch?v=yFIEqluoeGY

Gunkiemike wrote:

John, I know you know this, but your statement - as written - is what leads newbies to believe they can't tie a masterpoint in a Dyneema blend sling, or knot it in use at any time.

So, newbies realding this thread, better to say: Dyneema slings can't be cut e.g. to use as a rap sling, AND TIED BACK INTO A LOOP, as the knot will not hold.

Knotting ANY sling to shorten it is fine in normal climbing situations.

"Knotting ANY sling to shorten it is fine in normal climbing situations." Wrong. DMM has videos showing all the various ways slings can fail, and the most sobering finding was just adding a simple overhand in the middle of a 60cm Dyneema sling - it BROKE / failed, at the knot, in a factor ONE fall test. Visualize this clearly: you clip into a bolt at waist height with this arrangement, stand next to it so the slack hangs straight down, then step off the ledge, going all of 24," and sayonara, baby. What many fail to notice from firsthand experiences is that many "close calls averted" may be because you were standing away from the anchor, and what you took was actually a penduluming fall, which has a much lower peak force that straight drop. The rampant use of static synthetic slings into belay systems is senseless and always riskier than just using the main rope - which is usually at least as strong, and the primary dynamic material as well. Guides advancement of such tactics should be condemned; they developed such shortcut methods for expedience in transferring clients onto fixed anchors conveniently, where they can be supervised, but extending the use of dangerously static materials, with counter-intuitive properties like knot weakening means that hundreds of climbing teams are setting up ticking time bombs, until one small slip or shock reveals the true hazards. One YouTube "expert" proudly advances his use of clove hitches at sling attachment points, as a magical remedy for knot weakening, yet the DMM tests clearly show that to be a dangerous method as well. The numbers of accidents related to improper materials applications should be making every climbing agency or organization wake up and revise their negligent attitude about real safety margins.
This is not the same thing as discussing slings like the Edelrid or Mammut, which are reducing the risk from knotting, all well and good - the essentially static nature of the slings is the primary problem, as commonly used in "modern" anchor systems. Thinking of every such sling as a cable, can help you visualize where you are introducing inadvertent risks into what was once supposed to be the safety factor. When in doubt, use the lead rope.
An aside, few will be able to even cut any pre-sewn Dyneema sling with the average knife, so rejoining the ends is going to be moot. It is both the great compliment, and curse, that climbers are generally creative and innovative in using gear; the curse, is we don't pay attention to manufacturer's warnings, usage disclaimers, etc. and instead wing it. One can knot a Dyneema sling, clip in with shortening clove hitches, and belay directly off such things for years, catching normal minor falls, never fully shock-loading the dangerous system, and become complacent, convinced that just because what we've "always done" never failed, it therefore must be safe. I grew up in the flat Midwest, where mile square road grids crossed endless cornfields. Little traffic meant some would just blow through the stop signs at every mile, because the chance of another car crossing was low. One might do this for years, and never have a problem. Until you did, and you died. This is my analogy to using any static materials in anchors where inadvertent shock loading is a real possible risk. Think of every Dyneema sling as a steel cable, and you will have a way to clarify how and where you can safely incorporate them. The rope is still the strongest, most versatile, and dynamic tie-in material you are already carrying on the climb. Learn how to use it and wean away from overly complex, yet actually more marginal fancy multi-sling, pseudo-equalizing systems wherever possible.

Yeah, it seems like a good idea to use something other than skinny dyneema slings for belay anchors, PAS-type slings, etc. I picked up a few long nylon slings and Edelrid slings for that purpose years ago.